Roll-positioning mechanism



Oct. 25, 1966 F. K. QUALEY 3,280,610

ROLL-POSITIONING MEGHANI SM Filed Sept. 20, 1963 I/VVENTOR FRANCIS K. QUALEY Attorney United States Patent 3,280, ROLL-POSITIONENG MECHANISM Francis K. Qualey, Churchill Borough, Pa., assignor to United States Steel Corporation, a corporation of Dela- Ware Filed Sept. 20, 1963, Ser. No. 310,286 3 Claims. (Cl. 72245) This invention relates to an improved mechanism for positioning a roll in a roll stand.

Although my invention is not thus limited, the mechanism is particularly suited for positioning the lower work roll or back-up roll in a two-high or four-high roll stand. As rolls wear and are dressed down, their diameters of course decrease. To maintain the pass line at the same height, it is necessary to raise the lower rolls progressively as they become smaller. Conventional practice has been to employ shims for positioning the chocks in which the lower rolls are journaled, but this practice is awkward and time-consuming. Nevertheless it is apparent the mechanism can be adapted for other purposes, for example to replace the usual screw-down mechanism for positioning an upper roll.

An object of my invention is to provide an improved positioning mechanism which embodies hydraulic means for positively locking a roll in its adjusted position.

A more specific object is to provide an improved hydraulic positioning mechanism which includes a primary pump for roughly positioning a roll, intensifying pumps for precisely positioning the roll, and check valves for positively locking the roll in its adjusted position until released.

In the drawing, the single figure is a side elevational view, partly diagrammatic and partly broken away, of the lower portion of a roll stand equipped with a positioning mechanism constructed in accordance with my invention.

The figure shows a portion of a conventional roll stand which includes a pair of spaced-apart housings and 16a, a pair of lower roll chocks 12 and 12a mounted for vertical movement in the respective housings, a pair of upper roll chocks 13 and 13a mounted above the lower chocks, and lower and upper work rolls 14 and 15 journaled in the respective checks. The roll stand includes the usual other conventional parts which I have not shown, since they are not involved in the present invention. The stand can be equipped with a conventional screwdown mechanism for adjusting the upper roll, or alternatively with a hydraulic mechanism similar to that used for positioning the lower roll, hereinafter described. The two-high roll stand illustrated is only one example of the type of roll stand to which my invention is applicable, since the mechanism can be applied in the same way to other types, such as to a back-up roll of a fourhigh roll stand.

In accordance with my invention, I mount hydraulic cylinders 16 and 16a in the lower portion of the respective housings 10 and 10a beneath the lower roll chocks 12 and 12a. The cylinders contain vertically movable rams 17 and 17a, on which the chocks 12 and 12a rest, and glands 18 and 18a surrounding the rams. To these cylinders I connect a hydraulic circuit which includes a reservoir 19, a high volume primary pump 20, a motor 21 -for driving the pump, a proportioning valve 22, and branch pipes 23 and 23a leading from said valve to the respective cylinders. The circuit also includes high in tensity secondary pumps 24 and 24a connected to the respective branch pipes 23 and 23a via pipes 25 and 25a. The secondary pumps have drive motors 26 and 26a. I also connect release valves 27 and 27a and a dumping valve 28 to the branch pipes 23 and 23a. The two branch pipes contain respective check valves 29 and 29a located between the connection to the release valves and the connection to the secondary pump 24 or 24a.

To raise the lower roll 14, I operate the primary pump 29 to pump hydraulic fluid from reservoir 19 through the proportioning valve 22, branch pipes 23 and 23a and check valves 29 and 29a into cylinders 16 and 16a. The fluid acts on rams 17 and 17a to raise the roll approximately to the proper position. Subsequently I operate the secondary pumps 24 and 24b to force small quantities of hydraulic fluid through pipes 25 and 25a into the cylinders to raise the roll accurately to its final position. The secondary pumps are of a type which deliver small quantities of fluid under high pressure, whereby they can position the roll with great precision. One example of a suitable pump for this purpose is available commercially from Dynex Inc., Pewaukee, Wisconsin, and is described in a printed publication by the supplier, Specifica tion Sheet PF 3008, copyright 1958.

The release valves 27' and 27a and dumping valve 28 normally are closed. I can partially open either release valve as necessary in the event one end of the roll is raised too high or to lower the roll for any purpose. I open the dumping valve to relieve the portion of the hydraulic circuit beyond the check valves 29 and 29a. Thus the dumping valve enables the roll to be lowered quickly in the event of an emergency or for changing rolls. The check valves prevent fiuid from returning from the cylinders through the pumps and positively lock the roll in the position to which it is adjusted. Thus the entire roll stand can be shut down without affecting the setting.

While I have shown and described only a single embodiment of my invention, it is apparent that modifications may arise. Therefore, I do not wish to be limited to the disclosure set forth but only by the scope of the appended claims.

I claim:

1. In a roll stand which includes a pair of spaced-apart housings, roll chocks mounted ,in said housings for vertical movement, rolls journaled in said chocks, a pair of hydraulic cylinders mounted in the respective housings, and rams mounted in said cylinders for vertical movement and bearing against said chocks at opposite ends of one of said rolls for adjusting the position of this roll, the combination therewith of a hydraulic circuit comprising a reservoir of fluid, a primary pump connected with said reservoir, a proportioning valve connected with said pump and with both said cylinders for delivering fluid equally to each cylinder and moving said rams in one direction, a pair of high-intensity secondary pumps connected directly with said reservoir and with the respective cylinders in parallel with said primary pump and valve for delivering fiuid to said cylinders independently of said primary pump and of each other, said secondary pumps effecting fine adjustments in the positions of said rams in the same direction as said primary pump, a pair of release valves connected between the respective cylinders and said reservoir in parallel with said pumps for discharging fluid from said cylinders and moving said rams in the opposite direction from said pumps, and check valves connected between said cylinders and pumps to prevent return of fluid from said cylinders to said reservoir via said pumps.

2. A combination as defined in claim 1 in which said circuit also includes a dumping valve for relieving the portion of the circuit beyond said check valves and thereby moving the roll quickly in the opposite direction from said pumps.

3. A combination as defined in claim 1 in which the roll which is positioned by said mechanism is a lower pumps raises the roll.

References Cited by the Examiner UNITED STATES PATENTS Uren 72--245 Menne 72245 McIlvried 72--245 Cannon 60-97 4 2,678,465 5/ 1954 Schnuck 72-245 3,003,374 10/ 1961 Smith 72245 3,191,408 6/1965 B-ayan 724-245 FOREIGN PATENTS 1,213,820 11/1959 France.

CHARLES W. LANHAM, Primary Examiner.

H. D. HOINKES, Assistant Examiner. 

1. IN A ROLL STAND WHICH INCLUDES A PAIR OF SPACED-APART HOUSING, ROLL CHOCKS MOUNTED IN SAID HOUSINGS FOR VERTICAL MOVEMENT, ROLLS JOURNALED IN SAID CHOCKS, A PAIR OF HYDRAULIC CYLINDERS MOUNTED IN THE RESPECTIVE HOUSINGS, AND RAMS MOUNTED IN SAID CYLINDERS FOR VERTICAL MOVEMENT AND BEARING AGAINST SAID CHOCKS AT OPPOSITE ENDS OF ONE OF SAID ROLLS FOR ADJUSTING THE POSITION OF THIS ROLL, THE COMBINATION THEREWITH OF A HYDRAULIC CIRCUIT COMPRISING A RESERVOIR OF FLUID, A PRIMARY PUMP CONNECTED WITH SAID RESERVOIR, A PROPORTIONING VALVE CONNECTED WITH SAID PUMP AND WITH BOTH SAID CYLINDERS FOR DELIVERING FLUID EQUALLY TO EACH CYLINDER AND MOVING SAID RAMS IN ONE DIRECTION, A PAIR OF HIGH-INTENSITY SECONDARY PUMPS CONNECTED DIRECTLY WITH SAID RESERVOIR AND WITH THE RESPECTIVE CYLINDERS IN PARALLEL WITH SAID PRIMARY PUMP AND VALVE FOR DELIVERING FLUID TO SAID CYLINDERS INDEPENDENTLY OF SAID PRIMARY PUMP AND OF EACH OTHER, SAID SECONDARY PUMPS EFFECTING FINE ADJUSTMENTS IN THE POSITIONS OF SAID RAMS IN THE SAME DIRECTION AS SAID PRIMARY PUMP, A PAIR OF RELEASE VALVES CONNECTED BETWEEN THE RESPECTIVE CYLINDERS AND SAID RESERVOIR IN PARALLEL WITH SAID PUMPS FOR DISCHARGING FLUID FROM SAID CYLINDERS AND MOVING SAID RAMS IN THE OPPOSITE DIRECTION FROM SAID PUMPS, AND CHECK VALVES CONNECTED BETWEEN SAID CYLINDERS AND PUMPS TO PREVENT RETURN OF FLUID FROM SAID CYLINDERS TO SAID RESERVOIR VIA SAID PUMPS. 